Molecular Cloud Barnard 68 NASA March 23, 2008
Molecular Cloud Barnard 68 NASA March 23, 2008
Spacecraft chases highest night shining clouds clouds BBC - December 11, 2007
PhysOrg - April 20, 2007
Combining the world's largest radio telescope at Arecibo, Puerto Rico with a precision imaging, seven-antenna synthesis radio telescope at the Dominion Radio Astrophysical Observatory (DRAO), a team of researchers led by Los Alamos scientist Philipp Kronberg have discovered a new giant in the heavens, a giant in the form of a previously undetected cloud of intergalactic plasma that stretches more than 6 million light years across.
The diffuse, magnetized intergalactic zone of high energy electrons may be evidence for galaxy-sized black holes as sources for the mysterious cosmic rays that continuously zip though the Universe. In research reported in the April issue of Astrophysical Journal, the team of researchers from Los Alamos, Arecibo, and DRAO in Penticton, British Columbia describe their discovery of a 2-3 megaparsec zone of diffuse, intergalactic plasma located beside the Coma cluster of galaxies. The combined use of the 305 meter Arecibo radio telescope to make a base scan of 50 square degrees of sky, and the DRAO, making 24 separate 12 hour observations over 24 days of the same sky area, resulted in an image comparable to that of a 1000 meter diameter radio telescope. After Arecibo mapped the larger cloud structure, DRAO data was used to enhance the resolution of the image.
According to Kronberg, "One of the most exciting aspects of the discovery is the new questions it poses. For example, what kind of mechanism could create a cloud of such enormous dimensions that does not coincide with any single galaxy, or galaxy cluster? Is that same mechanism connected to the mysterious source of the ultra high energy cosmic rays that come from beyond our galaxy? And separately, could the newly discovered fluctuating radio glow be related to unwanted foregrounds of the Cosmic Microwave Background (CMB) radiation?"
The synchrotron-radiating plasma cloud is spread across a vast region of space that may contain several black hole harboring radio galaxies. The cloud may be evidence that black holes in galaxies convert and transfer their enormous gravitational energy, by a yet unknown process, into magnetic fields and cosmic rays in the vast intergalactic regions of the Universe.
Kronberg's work also provides the first preview of small (arc minute - level) features that could be associated with unwanted and confusing foregrounds to the CMB radiation. Because these same radiation frequencies are to be imaged by the PLANCK CMB Explorer, corrections to the observed CMB for foreground fluctuations (the so-called microwave "cirrus clouds") are vitally important to using CMB fluctuations as a probe of the early Universe.
Source: Los Alamos National Laboratory
Discovery - September 2004
Astronomers have found a sweet spot in a sublimely cold and vast interstellar cloud. An eight-atom called glycolaldehyde has been found residing at eight degrees above absolute zero in the Sagittarius B2 dust cloud, some 26,000 light-years from Earth. The sugar is just a few steps from ribose, an essential ingredient of DNA.
"This is a very cold cloud," said astronomer Philip Jewell of the National Radio Astronomy Observatory and part of the discovery team. "It's too cold for (the sugar) to have formed in that environment." Some sort of additional energy was needed to throw simpler molecules together to make the sugar, he said. What probably provided the sugar-making oomph was a shock wave from an exploding star, said Jewell. A shock wave would heat up pre-existing simpler molecules — water, ammonia, formaldehyde, methane, ammonia or carbon dioxide — so they could react and build the sugar. Once the reactions occurred, the molecules dispersed and cooled. The simpler molecules are thought to form on the surfaces of dust particles.
This is the second detection of glycolaldehyde in space, said Jewell, the first being in 2000, but a much warmer sugar, less revealing and a weaker signal. The glycolaldehyde was found using the Robert C. Byrd Green Bank Telescope in West Virginia to detect a radio signal emitted at a narrow and precise frequency when the sugar molecules rotate. The team's results appeared in the Sept. 20 issue of Astrophysical Journal Letters.
"This sugar is a relatively complex molecule," said astronomy professor Edward Churchwell of the University of Wisconsin in Madison. "The whole issue of complex molecules in interstellar space was thought in the 1970s to be impossible." It was thought impossible because space between stars in our galaxy is rife with various forms of radiation that tend to knock apart large clumps of atoms.
Today astronomers know that the gigantic dust and gas clouds within the Milky Way provide shelter from radiation for molecules. "There are regions in space that are protected from all this radiation," Churchwell said.
The discovery hints of a rich molecular soup floating in the clouds between stars, said Churchwell, in the very places where they are most likely to find their way onto new planets. Clouds like Sagittarius B2 are where stars, and their planets, are born, he said.
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